A duplicated small (pinky) finger (postaxial polydactyly) is the presence of an extra small finger. Learn more about the diagnosis of a duplicated small finger.
Key points
A duplicated small (pinky) finger is an extra small finger on one or both hands.
Small finger duplication is quite common. It is more common in individuals who are born male than those who are born female, and in children who are of African descent.
Diagnosis of a duplicated small finger involves a physical examination and treatment decisions are made by a paediatric hand surgeon.
The extra small finger can be treated by surgically removing it.
Introduction
What is a duplicated small (pinky) finger?
A duplicated small finger is an extra small finger on one or both hands. There are two types of small finger duplication.
In the first type, the extra small finger is well formed and has a bony connection to the primary small finger. This type is not common.
In the second type, the extra small finger is floppy, not well developed, and loosely connected to the main small finger by a thin stalk. The extra small finger may be so minor that it appears as a small bump on the side of the main small finger. This type is very common.
Small finger duplication is not harmful to your child.
Duplicated small finger with a bony connectionDuplicated small finger loosely connected by skin
Causes, Risk Factors, Prevalence
Causes of small finger duplication
The exact cause of small finger duplication is unknown. It is not caused by anything the mother did or did not do while pregnant.
Prevalence
Small finger duplication often runs in families. When they grow up, your child may also have children with small finger duplication.
Diagnosis
Diagnosis
A health-care provider can diagnose a duplicated small finger during a physical examination and treatment decisions are made by a paediatric hand surgeon. Most of the time, no further tests, such as X-rays, will be needed. If the extra small finger is well developed, X-rays will be taken to evaluate the bony connection. These X-rays will help the surgeon plan your child’s surgery.
Treatment
Treatment
The treatment for a duplicated small finger is surgical removal. There are two surgery options depending on your child’s age and whether the small finger is connected by a thin skin stalk or has a bony connection.
A duplicated small finger that is floppy can get caught in things like clothing while getting dressed. This can be mildly uncomfortable.
If the duplicated small finger is connected by a thin stalk of skin, it is possible that it can twist on itself, causing a lack of blood supply. This may make the extra small finger turn red or purple in colour. If the finger remains twisted for a long period of time, it may fall off naturally on its own. This is called autoamputation. If the finger autoamputates, there may be a remaining bump on the finger. The bump can be removed by a plastic surgeon if it is bothersome for your child, or for aesthetic reasons.
At Sickkids
At SickKids
Your child will visit the Plastic Surgery Clinic for their initial consultation, which includes a physical examination and discussion about treatment.